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<br />timing of critical habitat designation relative to listing. <br /> <br />In the Colorado River case, there was a substantial lag between listing the fish as endangered and <br />designating critical habitat (ranging from 26 years for the Colorado squawfish and humpback <br />chub to two years for the razorback sucker). As a result, most of the recovery plans for the fish <br />that generate impacts were either already prepared or in the planning stage before critical habitat <br />was designated.16 For this reason, only 10 percent of all combined impacts associated with <br />resource reallocations for the fish were attributed to critical habitat. In the Virgin River study, <br />however, the relatively close concurrence of listing and critical habitat designation led to <br />assigning 50 percent of combined impacts to each cause. <br /> <br />VI. Virgin River and Colorado River 1-0 Sub-regional and Regional Impacts <br /> <br />For the Virgin study there are two classes of direct impacts that arise from actions taken on <br />behalf of the fishes. The first class concerns impacts that are due to the conversion of water use <br />from agriculture to municipal and industrial uses. Such conversion will occur in the absence of <br />actions taken on behalf of the fish. However, the changes in the river flows necessary for <br />recovery of the fish will change the timing of the conversion of the agriculture water. Sets of <br />agriculture templates were developed and used to calculate the output changes that would result <br />from changes in the amount of irrigation water allocated to agriculture. These output changes <br />were entered directly into the 1-0 model in the manner of mixed exogenous-endogenous models <br />(or supply side and demand side models). Thus, the quantity of output for each of the affected <br />agriculture sectors was changed directly to reflect the particular scenario being investigated. <br /> <br />The second class of direct impacts arise from changes in the demands for goods and services <br />stemming from actions taken on behalf of the fishes. The changes in the river flows required for <br /> <br />16 At the time that each of the four Colorado fishes were listed, the Service reported that their habitat needs <br />were not determinable. Critical habitat designations were undertaken later as the result of a lawsuit filed by <br />environmental groups. <br /> <br />24 <br />